1. Field of the Invention
The invention relates to hydrolyzable and polymerizable and/or polyadditive silanes, to processes of their production and their use in the production of organically modified silicic acid polycondensates and/or hetero polycondensates, as well as to their use in the production of macromolecular compounds by polymerization and/or polyaddition.
2. The Prior Art
Hydrolyzable organically modified silanes are widely used in the manufacture of scratch-proof coatings for the most variegated substrates, in the production of fillers, of adhesive and caulking compounds, or of molded arcticles. In such processes, the silanes are hydrolytically condensed either by themselves, in mixtures or in the presence of further hydrolyzable and/or condensable components, with final curing being accomplished thermically, photochemically, or by redox induction.
Thus, scratch-proof layers are known from DE 3 407 087, which are formed by a hydrolytic condensation of a mixture consisting, among others, of a hydrolyzable titanium or zirconium compound and of a hydrolyzable organo-functional silane R'.sub.m (R"Y).sub.n SiX.sub.(4-m-n) in which R' is, for instance, an alkyl or alkenyl, R" is, for instance, an alkene or alkenylene and X is a hydrolyzable group.
From DE 3,536,716 A1, adhesive and caulking compounds, for instance, are known which have been made by hydrolytic condensation of one or more organo-silanes of the general formula R.sub.m SiX.sub.4-m and, where desired, of one or more of components like SiX.sub.4 and/or R.sub.n (R"Y).sub.p SiX.sub.4-n-p, where R and R" are, for instance, an alkyl, alkenyl, aryl, alkylaryl, arylalkyl, alkenylaryl or arylalkenyl, X is, for instance, hydrogen, halogen, hydroxy, alkoxy or acyloxy, and where Y is, for instance, a halogen or a possibly substituted amino, amide, aldehyde, alkylcarbonyl, carboxy, hydroxy, mercapto or cyano group.
Furthermore, commercial silanes with reactive double bonds are known, as, for example, (meth)acryloxysilanes of the following type, ##STR2##
where R is hydrogen or methyl and X is, for instance, a halogen or alkoxy. These silanes are hydrolyzable and polymerizable and may be used for producing the above-mentioned systems. They offer the great advantage that the resultant coating, the resultant filler, adhesive or caulking compound or the resulatant molded article may be cured thermically, photochemically or by redox induction by polymerization at the double bonds.
Commercial silanes with reactive double bonds, such as, for instance, the (meth)acryloxysinales referred to above, generally are monofunctional compounds with a C.dbd.C double bond, and are usually low molecular and thus, prior to the Si--X hydrolysis and condensation, relatively volatile compounds which give rise to toxicological concerns because of their acryl group. During further processing by polymerization or modified functionalization these silanes suffer from the further disadvantage that because of the single reactive C.dbd.C double bond only chain polymers can be produced and that with prior functionalization, the C.dbd.C double bond required for the organic polymerisation is usually lost. Furthermore, a short chain only is usually present between the double bond and the silicon capable of forming an anorganic network, so that on the basis of the organic groups the mechanical characteristics (flexibility, etc.) may be varied within very narrow limits only.
While hydrolyzable and polymerizable silanes provided in their molecule with a norbornene group are known from EP 0,388,028 A2 and EP 0,439,650 A1, there is still a need for improvements, including in respect of a functionalization of the molecule.